refactor: bottom group blueprint

lib/game/components/bottom_group.dart

@@ -1,6 +1,7 @@
 import 'package:flame/components.dart';
 import 'package:pinball/game/game.dart';
 import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_flame/pinball_flame.dart';
 
 /// {@template bottom_group}
 /// Grouping of the board's symmetrical bottom [Component]s.
@@ -8,21 +9,15 @@ import 'package:pinball_components/pinball_components.dart';
 /// The [BottomGroup] consists of [Flipper]s, [Baseboard]s and [Kicker]s.
 /// {@endtemplate}
 // TODO(allisonryan0002): Consider renaming.
-class BottomGroup extends Component {
+class BottomGroup extends Blueprint {
   /// {@macro bottom_group}
-  BottomGroup() : super(priority: RenderPriority.bottomGroup);
-
-  @override
-  Future<void> onLoad() async {
-    final rightSide = _BottomGroupSide(
-      side: BoardSide.right,
-    );
-    final leftSide = _BottomGroupSide(
-      side: BoardSide.left,
-    );
-
-    await addAll([rightSide, leftSide]);
-  }
+  BottomGroup()
+      : super(
+          components: [
+            _BottomGroupSide(side: BoardSide.right),
+            _BottomGroupSide(side: BoardSide.left),
+          ],
+        );
 }
 
 /// {@template bottom_group_side}
@@ -34,7 +29,8 @@ class _BottomGroupSide extends Component {
   /// {@macro bottom_group_side}
   _BottomGroupSide({
     required BoardSide side,
-  }) : _side = side;
+  })  : _side = side,
+        super(priority: RenderPriority.bottomGroup);
 
   final BoardSide _side;
 

lib/game/pinball_game.dart

@@ -47,7 +47,7 @@ class PinballGame extends Forge2DGame
     unawaited(add(CameraController(this)));
     unawaited(add(Backboard.waiting(position: Vector2(0, -88))));
     await add(Drain());
-    await add(BottomGroup());
+    await addFromBlueprint(BottomGroup());
     unawaited(addFromBlueprint(Boundaries()));
     unawaited(addFromBlueprint(LaunchRamp()));
 

test/game/components/bottom_group_test.dart

@@ -4,6 +4,7 @@ import 'package:flame_test/flame_test.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:pinball/game/game.dart';
 import 'package:pinball_components/pinball_components.dart';
+import 'package:pinball_flame/pinball_flame.dart';
 
 import '../../helpers/helpers.dart';
 
@@ -21,10 +22,8 @@ void main() {
     flameTester.test(
       'loads correctly',
       (game) async {
-        final bottomGroup = BottomGroup();
-        await game.ensureAdd(bottomGroup);
-
-        expect(game.contains(bottomGroup), isTrue);
+        await game.addFromBlueprint(BottomGroup());
+        await game.ready();
       },
     );
 
@@ -32,13 +31,12 @@ void main() {
       flameTester.test(
         'one left flipper',
         (game) async {
-          final bottomGroup = BottomGroup();
-          await game.ensureAdd(bottomGroup);
+          await game.addFromBlueprint(BottomGroup());
+          await game.ready();
 
-          final leftFlippers =
-              bottomGroup.descendants().whereType<Flipper>().where(
-                    (flipper) => flipper.side.isLeft,
-                  );
+          final leftFlippers = game.descendants().whereType<Flipper>().where(
+                (flipper) => flipper.side.isLeft,
+              );
           expect(leftFlippers.length, equals(1));
         },
       );
@@ -46,12 +44,12 @@ void main() {
       flameTester.test(
         'one right flipper',
         (game) async {
-          final bottomGroup = BottomGroup();
-          await game.ensureAdd(bottomGroup);
-          final rightFlippers =
-              bottomGroup.descendants().whereType<Flipper>().where(
-                    (flipper) => flipper.side.isRight,
-                  );
+          await game.addFromBlueprint(BottomGroup());
+          await game.ready();
+
+          final rightFlippers = game.descendants().whereType<Flipper>().where(
+                (flipper) => flipper.side.isRight,
+              );
           expect(rightFlippers.length, equals(1));
         },
       );
@@ -59,11 +57,10 @@ void main() {
       flameTester.test(
         'two Baseboards',
         (game) async {
-          final bottomGroup = BottomGroup();
-          await game.ensureAdd(bottomGroup);
+          await game.addFromBlueprint(BottomGroup());
+          await game.ready();
 
-          final basebottomGroups =
-              bottomGroup.descendants().whereType<Baseboard>();
+          final basebottomGroups = game.descendants().whereType<Baseboard>();
           expect(basebottomGroups.length, equals(2));
         },
       );
@@ -71,10 +68,10 @@ void main() {
       flameTester.test(
         'two Kickers',
         (game) async {
-          final bottomGroup = BottomGroup();
-          await game.ensureAdd(bottomGroup);
+          await game.addFromBlueprint(BottomGroup());
+          await game.ready();
 
-          final kickers = bottomGroup.descendants().whereType<Kicker>();
+          final kickers = game.descendants().whereType<Kicker>();
           expect(kickers.length, equals(2));
         },
       );